By Lars Mucklejohn Standard Chartered has said it will double investment in its wealth management arm as the bank beat estimates for its third-quarter profit and boosted plans for shareholder returns. The FTSE 100 lender, which focuses on emerging markets, reported a pretax profit of $1.72bn (£1.3bn) between July and September, topping analysts’ forecasts of $1.49bn (£1.1bn). Its profit was nearly triple the $633m (£487m) reported during the same period last year when the bank took almost $1bn (£800m) in impairment charges from its exposure to China’s sluggish economy. Standard Chartered raise…